Starting JBoss-5 CR1, the jbossall-client.jar is a Manifest only jar. I don't have access to my system right now, but i remember that the jbossall-client.jar in CR1 had a ReadMe inside it, which tells you which all jars you need to copy in the client's classpath. anonymous wrote : | we are not able to retreive JMS Data, we got the following exception like this | | "jboss.mq:service=MessageCache is not registered" I am not sure whether this exception is because of the missing jar files. You will have to post the entire exception stacktrace. Where does this exception occur? Is it on the client or on the server? View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4170216#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...